Top beam clamp

ABSTRACT

A pipe hanger clamp, formed by bending a flat section of metal bar or plate, has two vertical side members which have been cut so their side view is a “C” shape. The lower arms of these two side members are joined by a horizontally extended end wall, about which the side members are bent. Holes in the end wall receive a mounting set screw into a captured nut and another nut to hold a pipe hanger rod for supporting a pipe. An overhead support is clamped between the set screw and the upper arms of the C-shaped side members, such that the load applied to the rod is generally edgewise to the plate thickness, and does not provide an unbending force on the clamp.

TECHNICAL FIELD

This invention relates to an improved clamp to attach pipe hangers tooverhead structures, and relates to an improved method of making such aclamp.

In the construction and modification of buildings, it is often desirableto suspend piping from the ceiling, one common example being watersprinkler systems. A typical method for attaching a pipe to the ceilingutilizes the flanges of the ceiling support beams. A pipe hanger clampfits over the edge of one of these flanges, and a pipe hanger rodattached to the clamp supports the pipe. This method is convenientbecause it permits the pipes to be hung after the building has beenconstructed.

BACKGROUND ART

A number of clamps have been developed, three of which are disclosed inU.S. Pat. No. 4,570,885, U.S. Pat. No. 3,276,800, U.S. Pat. No.3,211,161, and U.S. Pat. No. 3,572,623. These four patents generallyindicate the state of the prior art. One approach to the manufacture ofthese clamps utilizes casting. A cast clamp has significant torsionalstiffness. However, this manufacturing process is costly and laborintensive. Another approach contemplates plastically deforming a stripof material, usually steel, into a “U” shape. A hole is drilled into oneof the arms of the clamp, and the hole is tapped to accommodate a setscrew. When attached, the clamp is oriented so that the rounded portionis directly next to the tip of the supporting flange. This type of clampcan be manufactured inexpensively. However, unless made relatively thicksteel, such a clamp the threaded connection tends to deform under heavyloading. Making the part thick enough to have sufficient threads to bearthe load is the problem as the steel structure of the clamp would besufficient in lighter and less costly gages of metal. Some manufacturershave used a friction drilling method to push metal to form a longerthread engagement (see FIG. 2 as prior art). This method marginallyworks but takes time to process as the metal must be friction heated tonear molten state. The current invention traps ordinary nuts or othersimilar fasteners with full-length threads into the part. It may furtherallow the rod hanger to move and comply with shifting loads thus takingthe stress off the clamping connection to the beam.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a pipehanger clamp having two cantilevered support arms with clamping surfacesfor engaging the same side of an I-beam. The relatively thin supportarms have a height which is significantly greater than their width.However, because the support arms are a distance apart, the clamp issecurely engaged with the supporting I-beam.

An end wall rigidly joins the two side members. A hole with a threadedfastener in the end wall accommodates a set screw for securely engagingthe support arms with the I-beam. A second hole with a threaded fastenerreceives a threaded section of a pipe hanger rod.

In accordance with the method of the invention the clamp is manufacturedfrom a single piece of flat metal bar stock. The plate is first blankedinto the desired shape, preferably an “E” shape. The workpiece issubsequently bent into a “U”-shape about the middle tine of the “E” toform the clamp, which has two side members having a general C-shape. Twothreaded receptacles are then inserted into the lower portion of theC-shape and trapped into the C-shape.

The female receptacle for the hanger rod is allowed to be not rigid andcomplies with movement of the installed hanger rod.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an isometric view of the preferred embodiment of the inventionshowing a typical use suspended on the top edge of a beam and connectingto a threaded hanger rod then to a clevis type pipe hanger.

FIG. 2 shows prior art with thermally extruded threaded portion.

FIG. 3 shows the freedom of movement of the hanger rod so as to relievestresses on the clamp.

FIG. 4 is an end view of the clamp showing the section line locationsfor FIGS. 5 and 6.

FIG. 5 is a section view showing hex nuts as threaded receptacles forthe rod and clamping set screw.

FIG. 6 is a section view showing the nut receptacles entrapped in theclamp.

FIG. 7 is an isometric view of the bare clamp body showing the variousfeatures used to trap the female threaded receptacles.

FIG. 8 is an isometric view of the clamp with a clip holding the nuts inplace.

FIG. 9 is a view of a typical clip.

FIG. 10 is an isometric view of the clamp with a bar nut instead for ahex or square nut.

FIG. 11 is a view of the typical bar nut with 2 tapped holes.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows the principal embodiment of the invention, as it would betypically used. Here it is attached to the top of an “I” shaped beam 5with an attached rod to which is suspended a clevis hanger 6 (U.S. Pat.No. 2,714,497). The set screw 7 is here shown with a locking nut 4 toaffix the clamp more reliably as the design requires that the clampshould be applied with a limited torque to the clamp 8 so as not todistort the clamp or over stress it. The lock nut 4 is then applied toprevent the set screw 7 from loosening due to any structural vibration.

FIG. 3 shows the added motion available with the preferred embodiment ofthis invention to allow for movement of the hanger rod 9 through andwithin circumference 22. Compare this to FIG. 2, (prior art) in which arigid thread is formed into the clamp. This rigidity forces the sway ofthe hanger to dislodge the clamp from its anchorage, which is held onlyby clamp friction on the attached beam. Using independent nut fastenersthis design is more flexible in its application and less expensive inits construction.

In FIG. 7 one can see some embodiments of the invention in the variousforms of embossments or lances which can be used to entrap the nutsthese include but are not limited to: a rib 11, a bent edge 12 andmultiple dimples 13. These features trap the nuts so they stay in placeduring the application of the clamp and in transport. Actualinstallation then traps and holds the components in final assembly.

In FIG. 4 one embodiment of the invention indicates the cut lines of thecross sectional views which follow. The first cross sectional view FIG.5 shows a cut away of the clamp showing how the nuts 8 and 10 are seatedin the clamp. Rod 9 is threaded to nut 8 to support the load while nut10 is used to hold back set screw 7 against that which is clamped beingheld tightly by locking nut 4. Since nut 8 is not firmly held in theclamp some uplift from the pipe hanger rod would not dislodge the clamp.If desired however a lock nut could be added to restrict a limitedamount of upward thrust. The open end of the clamp allows for verifyingthe full thread engagement of the hanger rod. While FIG. 6 shows how therib 11 and bent edge 12 entrap the nuts so they don't fall out duringtransport of the product to the end user.

FIG. 8 shows another embodiment of the invention. Here a clip 14 is usedto restrain the nuts in the clamp during shipment and installation. Onceinstalled however the clip adds no structural additions to the clamp.The clip may be made from metallic or non metallic materials Thisembodiment is just another way to allow the hanger rod to have somelimited movement. FIG. 9 shows one of many embodiments of the clipdesign.

FIG. 10 shows a further embodiment of the design. Here a bar nut as seenin FIG. 11 is inserted in the base of the U shape being trapped by theset screw.

This design, while easy to assemble, restricts the ability of the hangerrod to move as shown in FIG. 3. This design, may though, allow lowerinitial tooling and assembly machine costs.

By automatically inserting the nuts and or nut plates and set screwrequired during the manufacture of the clamp and by making the productout of pre-galvanized material and utilizing already availablecommercial fasteners, these designs afford substantial cost reductionsto the end user. This invention is beneficial and a clear replacementfor the currently imported cast versions or other pre-threaded versionsof the product. Concurrently the non-rigid connection of the hanger rodin the non bar versions afford a more reliable connection to the beamduring stress and vibration periods at no additional cost to the enduser. The invention presented here offers substantial engineeredimprovements both in cost and functionality over existing designs.

What is claimed is:
 1. A method of forming and assembling a pipe hangerclamp body comprising; blanking a metal plate into generally an E-shape,having a main body portion, a middle tine and a pair of end tines, saidblanking step including cutting the middle tine to form straight edgeseach parallel to and facing a straight edge on a respective one of saidend tines, said blanking step further including cutting said tines sothat the dimension of said middle tine perpendicular to said edges isconsiderably greater than the dimension of said end tines perpendicularto said edges, and said blanking step further including cutting theouter edges of said end tines, remote from said middle tine, so thatsaid outer edges taper towards the tips of said outer tines so that theouter tines are wedge-shaped and having two holes for fasteners in thecentral E tine spaced apart; embossing the part with features to entrapfemale threaded receptacles; bending the plate about the middle tine ofthe E-shape to form a generally U-shaped clamp with a portion of themiddle tine forming the bight or end wall of the U-shape and with theremainder of the E-shape forming the legs of the U-shape, each legforming a generally C-shaped side member joined by the end wall with theportions of the middle tine forming lower support arms of the C-shapedmembers and with the end tines forming the upper arms of the C-shapedmembers adding indents of various shapes to trap two threadedreceptacles such that they cannot rotate but yet may still moveangularly about the base for the U-shaped bottom of the clamp; insertingand trapping a female threaded receptacle up to the holes in the centerE-tine and inserting a set screw extending towards said upper arms sothat an upper arms so that an overhead support may be clamped betweenthe set screw and said upper arms; and inserting and trapping anotherfemale threaded receptacle up to the hole in said end wall for receivinga pipe hanger rod, the axis of the rod hole being approximately alignedwith the portions of said C-shapes that were formed by the main bodyportion of the E-shape.
 2. A pipe hanger clamp assembly prepared by themethod of claim
 1. 3. A method of forming and assembling a pipe hangerclamp body comprising; blanking a metal plate into generally an E-shape,having a main body portion, a middle tine and a pair of end tines, saidblanking step including cutting the middle tine to form straight edgeseach parallel to and facing a straight edge on a respective one of saidend tines, said blanking step further including cutting said tines sothat the dimension of said middle tine perpendicular to said edges isconsiderably greater than the dimension of said end tines perpendicularto said edges, and said blanking step further including cutting theouter edges of said end tines, remote from said middle tine, so thatsaid outer edges taper towards the tips of said outer tines so that theouter tines are wedge-shaped and having two holes for fasteners in thecentral E tine spaced apart; bending the plate about the middle tine ofthe E-shape to form a generally U-shaped clamp with a portion of themiddle tine forming the bight or end wall of the U-shape and with theremainder of the E-shape forming the legs of the U-shape, each legforming a generally C-shaped side member joined by the end wall with theportions of the middle tine forming lower support arms of the C-shapedmembers and with the end tines forming the upper arms of the C-shapedmembers; inserting and trapping a female threaded receptacle using aclamp strap bent around the base of the so as to entrap the threadedfemale receptacles against the holes in the center E-tine and insertinga set screw extending towards said upper arms so that an upper arms sothat an overhead support may be clamped between the set screw and saidupper arms; and inserting and trapping another female threadedreceptacle within the strap up to the hole in said end wall forreceiving a pipe hanger rod, the axis of the rod hole beingapproximately aligned with the portions of said C-shapes that wereformed by the main body portion of the E-shape.
 4. A pipe hanger clampassembly prepared by the method of claim
 3. 5. A method of forming andassembling a pipe hanger clamp body comprising; blanking a metal plateinto generally an E-shape, having a main body portion, a middle tine anda pair of end tines, said blanking step including cutting the middletine to form straight edges each parallel to and facing a straight edgeon a respective one of said end tines, said blanking step furtherincluding cutting said tines so that the dimension of said middle tineperpendicular to said edges is considerably greater than the dimensionof said end tines perpendicular to said edges, and said blanking stepfurther including cutting the outer edges of said end tines, remote fromsaid middle tine, so that said outer edges taper towards the tips ofsaid outer tines so that the outer tines are wedge-shaped and having twoholes for fasteners in the central E tine spaced apart; bending theplate about the middle tine of the E-shape to form a generally U-shapedclamp with a portion of the middle tine forming the bight or end wall ofthe U-shape and with the remainder of the E-shape forming the legs ofthe U-shape, each leg forming a generally C-shaped side member joined bythe end wall with the portions of the middle tine forming lower supportarms of the C-shaped members and with the end tines forming the upperarms of the C-shaped members; inserting a double female threaded insertinto the base of the C-shaped member so as align the holes with those inthe center E-tine and inserting a set screw extending towards said upperarms so that an upper arms so that an overhead support may be clampedbetween the set screw and said upper arms.
 6. A pipe hanger clampassembly prepared by the method of claim 5.